如何通过双击从Eclipse运行导出的.jar？

I exported a runnable .jar file for a project of mine in Eclipse, but I can't seem to execute it with a double click. Running it from the command line with "java -jar program.jar" works fine, and while I could just leave a batch file to run it, it is rather annoying to do so. And double clicking some older jars that i've exported from Eclipse works fine. Anyone know how to fix this? I'm running windows 7 x64 btw(But i have 32-bit java)I exported a runnable .jar file for a project o